Subject: Re: A24 access with 32MB onboard?
To: Steve Woodford <scw@netbsd.org>
From: None <Henning.Kiel@physik.uni-dortmund.de>
List: port-mvme68k
Date: 04/02/2004 15:37:57
Hi,

I need A24D8 access. How can I get that?

maybe I misunderstood the following...

On Wed, 26 Nov 2003, Steve Woodford wrote:

> There is usually one default A24 window at 0xf0000000, but this is D16
> only. If you want a D32 window, you'll need to configure one manually
> from 167-Bug, as follows:
>
> 167-Bug> env
> ...
> Master Enable #1 [Y/N] = Y?
> Master Starting Address #1 = 02000000?
> Master Ending Address #1   = EFFFFFFF? eeffffff		<--- change
> Master Control #1 = 0D?
> Master Enable #2 [Y/N] = N? y				<--- change
> Master Starting Address #2 = 00000000? ef000000		<--- change
> Master Ending Address #2   = 00000000? efffffff		<--- change
> Master Control #2 = 00? 3d				<--- change
> Master Enable #3 [Y/N] = N? .				<--- exit

0x0D is "A32 supervisory data access"
0x3D is "A24 supervisory data access"

So, master#1 is A32 and master#2 is A24.
But how do I know which Dxx that is?

I need A24D8 access for certain card.


> The above example will free up 16MB at the top of the existing A32/D32
> window (Master #1), and create a new A24/D32 window in that free space
> using Master #2. (Note: depending on how your mvme167 was configured

ok, that's baiscally what I wrote above.

> previously, you might see different values for the Master windows. I
> suggest making sure Masters #3 and #4 are disabled, and that #1 and #2
> match the above example.)
>
> So, you now need to mmap two regions in your program:
>
> 	0xf0000000 x 16MB	A24/D16
> 	0xef000000 x 16MB	A24/D32
> Both regions map to A24 address space, but with different data sizes.